In the course of the last decade particularly, an increasing attention is being devoted to the preparation and utilization of artificial perfuming- and odour-modifying agents possessing the skeleton of tricyclo[5.2.1.0..sup.2,6 ]decane. This attention has certainly been stimulated mainly by an increased availability of the compounds acting as starting materials in the aforementioned preparations.
It has been shown for instance (see German Pat. No. 1,617,021) that the compounds of formula ##SPC3##
Wherein R represents an acyl group or a hydrogen atom, possess a perfuming note reminiscent of that developed by lavender oil. According to laid open to public inspection Dutch Patent Application No. 6901750, the polycyclic .gamma.,.delta.-unsaturated aldehyde of formula ##SPC4##
Develops a green-fruity character which is reminiscent of the lily-of-the-valley fragrance.
3A,4,7,7A-Tetrahydro-4,7-methanoindene and 2,3,3a,4,7,7a-hexahydro-4,7-methanoindene have been also described as compounds possessing an interesting marked woody character (see: U.S. Pat. No. 3,542,877).
We have now surprisingly found that the compounds of formula I possess interesting organoleptic properties and, accordingly, are useful ingredients in the perfumery and in the flavour industry.